Vehicle drive system

A vehicle drive system comprising:

• a motor that has a cylindrical stator and a cylindrical rotor rotatably provided in the stator to be coaxial with a center axis of the stator and that drives a drive wheel of a vehicle by rotation of the rotor,
• the rotor having:
• secondary conductors that extend in an axial direction and aligned in a circumferential direction in a radially outer portion;
• and permanent magnets that extend in the axial direction and aligned in the circumferential direction in a portion on a radially inner side of the secondary conductors,
• circuitry configured to switch a drive mode of the motor between a synchronous operation mode and an asynchronous operation mode, wherein
• the circuitry is configured to determine whether a required torque for the motor is greater than an allowable limit torque in the synchronous operation mode, and determine whether an actual operating temperature of a permanent magnet of the rotor is lower than an allowable lower limit temperature, and
• wherein the circuitry is configured to intentionally select the asynchronous operation mode when the required torque is greater than the allowable limit torque or when the actual operating temperature is lower than the allowable lower limit temperature, so as to allow a torque pulsation of the motor.